Extensible micrometer caliper



P. LusTmK.

EXTENSIBLE MICROMETER CALIPER.

APPLICATION HLED JULY 5.1919.

19425,@2?. @mmm-8, 19522.

i Hinwil" nih e ,vos H elfe PETER LUSTRK, OF CLEVELLED, 01H10.

Application filed. July 5, 1919.

To all "ro/7mm t may concer/a Be it known that L PETER LUsrnin, citizen of the United Statesj residingat Cleveland. in the county ot Cuyahoga and State of Ohio, have invented certain new and useful improvements in Extensible Microineter Calipers, ot Which the following is a specilication.

rlhis invention relates to micrometer calipers of the extensible type.

The object of the invention is to produce a micrometer caliper having a Wide range of adjustments and utilizable 'throughout its full range of adjustment either for talring accurately the size of an article or for setting the caliper to any desired definite sizev and in which the parts are of' simple construction, can be readily assembled, can be adjusted to maintain accuracy in spite of Ycar7 and in which lost motion or play between the caliper jaws is avoided by solid mounting of said javrs and the application of adjusting pressure thereto between the supports therefor so as to avoitL cooking of the jaws on the supports.

Further objects o t the invention are in part obvious and in part Will appear more in detail hereinafter.

ln the drawings, -which represent one embodiment or" the invention, Fig. 1 is a side elevation; Fig. 2 is a cross section on the line 2 2, 1; 3 is a similar view on the line 3-8, Fig. 1; Fig. l is a similar view on the line l-e, Fig. 1; and Fig. 5 is a longitudinal section on the line 5-5,

The calipers shown in the drawings comprise a rigid trame oit suitable forni including a head 1 to which are connected a pair of parallel guide bars or members 2connected at their outer ends by a bridgije 8. so as to forni. a substantially rectangular frame. The guide members 2 may be rods or bars oit any suitable length press fitted, soldered., Welded or brazed into openings in the head and bridge, as desired, and oi suiliciently large size to avoid lateral bending' thereof such as might interfere with the accuracy of the device or free slide of the slide members thereon.

Gn the guide bars 2 are mounted a pair of slides 1, 5, which oi course are placed on said guide bars before the 'frame is completely assembled. Slide l is next adjacent to the head 1 and has an outwardly extending, jaw portion G cooperating with a like .iti-Jn of Letters Patent. Pg'wtieiitetl Serial No. 308,883.

jaw portion 7 of the heath and between v-rhieh portions the Work to be calipered inserteth as is usual. Said slide also has a sleeve portion S surrounding one of' the rods 2 and a second sleeve portion 9 surrounding the other rod 2, said latter sleeve being` split and provided with clamping' ears 10 to receive the clamping screw 11. By turning up this screv7 the slide 1lmay be locked in any position along the rods to Which it may be adjusted.

Slide 5 has a sleeve 12 sliding' on one avv 2 and a split sleeve portion 18 sliding on the other rod 2 and provided with ears lil and a clamping' screw 15. One of the sleeve portions of the slide 5 may be provided with suitable,indicating member co-operatingr with a series o'l' indicating marks 1G spaced at intervals along one o the rods This indicating device may be a pointer or an index mark 1T on the sleeve 12 lying' at one edge of a sight opening 18 in the sleeve through which marks 1G are visible.

The tivo slides l and 5 are connected by micrometer mechanism oi ordinary iorm. Said mechanism includes a body portion 19 solidly secured to the slide 5. This body portion is of sleeve form and may be secured to the slide 5 by being press fitted to an opening therein. Body 19 has the usual indicating` marks 2O distributed along` its length and is externally threaded to receive the threads oit a barrel member 22 surrounding' the body 19 and eonnectecL to a rod 21. lod 2i'. turns with the rotating; barrel and extends through the sleeve 19 to the slide d where it is provided with a head 23 su'iveled or rotatably connected to said slide. As illustrated the head 23 turns in a slot or opening 24- betu'een the body ot the slide '-i and a plate connected thereto by screws 26. rthe ends ol. said plate are cnt olli' on an angle, as at 27.

Bridge member 3 may have an opening 28 in its central 'iortion throuoh which the 1 a b oarrel 22 oic the micrometer mechanism may extend, so as to enable the slide 5 to be brought closer to the bridge than' Would otherwise be the case.

The caliper is used as follows: Let us assume that the micrometer mechanism has a capacity or is adjustable through a range oi' one-half inch. ln this case the indicating; marks 16 on the rod 2 are located one-halt inch apart along the length of said iod. To set the caliper to any given dimensions, say

two inches, both clamping screws ll, i5 are loosened, the micrometer mechanisml is set at Zero and slide 5 is adjusted until its -indi'- cating mark 17 registers with the two inch mark on the rod 2. Clamping screws 1l and l5 are then tightened tohold both slides in adjusted position. ly rotating the barrel 22 any additional amount over two inches may be added to the two inches already secured, according to the proper adjustment ot the micrometer barrel. Adjustment ot said barrel with the slide 5 fixed will move the slide 4 to the right in Fig. l.

lf the size of a given article is to be determined the micrometer is set vat Zero, both clamping screws are loosened and the jaws 6', 7 set to embrace the article to be measured.

Clamping screw 'l1 is then turned up to fix the jaw e in position. indicating mark 17 will then lie between two of the marks 16 upon the rod 2, and by turning the microm ter barrel to move the slide until its indicating mark 1"( registers with the neat inarlr 16 of lower value ythe additional amount above said lower value can be read on the micrometer device.

The pressure ot the micrometer mechanism in adjusting` the two slides relative to each other is transmitted to said slides midway between their supports on the guide rods, so that there is no tendency olf the slides to stick on the guide rods or to become cocked or tilted thereon as is thev case when the micrometer mechanism is at one side olf the guides.

The construction also insures accuracy since the device is adjustable to do away with lost motion between the swivel head oi' the micrometer device and the slide 4t. Betweenr said headv and the slide l there should be no lost motion longitudinally ot' the mechanism, and such lost motion can be avoided even it wear occurs by taking oil the plate 25 and lapping` olf or grinding its beveled ends 27 to adj ust it into closer contact with the head 23.

lVhat l claim is:

l. An extensible micrometer caliper, comprisingl a rigid 'frame including two parallel guide members, a bridge permanently con necting;` said members at one end, a stationary jaw permanently connecting said members at the other end, a pair olislides movable on said guide members and permanently retained thereon by said bridge and jaw, one of said slides having a jaw for co-operation with said stationary jaw and lying` between anism lyingl between said guide members.,vv

said mechanism including a body rigidly se-v cured to one slide, an adjustable barrel member cooperating therewith and having a rod extending-'to the other slide, and a head on said rod rotatably connected to the other slide.

3. An extensible micrometer cali-per, comprising` a rigid frame including two parallel guide members and a stationary jaw, a pair of slides movable on said guide members, one thereof having a jaw, and micrometer mechanism lying between said guide members said mechanism including a body rigidly secured to one slide, an adjustable barrel meinber cooperating. therewith and. having a rod extendingl to the other slide, a head on said rod lying,V in a recess ot the other slide, and a removable plate securing` said head rotatably in said recess.

d. An extensible micrometer caliper, comprising a rigid trame including twoparallel guide members and a stationary jaw, a pair of slides movable on said ,guide members, one thereot having a jaw, and micrometer mechanism lying between said guide members, said mechanism including a body rigid-ly secured to one slide, an adjustable barrel-linember cooperating therewith and having, a rod extending; to the other slide, a head on said rod lying,- in a recess oig theother slide, and a. removable plate securing said head rotatably -in said recess, said plate having,` beveled end portions.

5. An extensible micrometer caliper, -comprising a pair olt parallel guide members rigidly connected at one end by a head having a jaw portion and at the other. end by a bridge having,r a central.. opening'k a pair oil slides movable on said `guide members, one o'lE which has a aw portion, and micrometer mechanism con nectmg said slides and lying between rsaid guide members, the. barrel thereof extending` toward said bridge and being movable through the opening thereof.

ln testimony whereotl l atlix my signature.

rnrnn Lnsreni. 

